It has long been known that the usual means of cleaning teeth, such as by a toothbrush and toothpaste, leaves a great deal to be desired insofar as removing bacteria, plaque, and other foreign matter is concerned. To properly clean teeth, one must in addition use dental floss. With proper use of dental floss employing adequate manual dexterity over sufficient time along with brushing, adequate tooth cleaning can be accomplished. However, it has been well established that most people do not have the required manual dexterity or refuse to spend the amount of time necessary to properly clean their teeth. To solve some of the problems relating to the ineffectiveness of the toothbrush and toothpaste tooth-cleaning means, apparatus applying pulsating water or liquid to the teeth and gums was generated. Although such a device assisted in cleaning the mouth, it was still found not to be effective insofar as matter secured to the teeth is concerned.
Ultrasonic tooth-cleaning apparatus was then invented for use in cleaning the surface of the teeth. This apparatus included the insertion of an ultrasonic generating means into the mouth cavity which had been partly filled with a liquid to serve as a medium for the transmission of sonic energy from the transducer throughout the mouth cavity to the surfaces of the teeth. In addition thereto, ultrasonic energy has also been utilized to vibrate a mechanical member such as a pick or other tool to loosen calculus from the surface of the teeth.
Such prior-art apparatus although somewhat effective either required use by a highly trained person, such as a dentist or hygienist, to preclude damage to the gingival and non-gingival areas of the mouth, or required the insertion into the mouth of the active portions of the ultrasonic generator. In some instances, the ultrasonic radiating surface has been inserted into the mouth of the user in such a manner that the radiated energy is ineffectively applied to the teeth and/or is allowed to impact upon other areas of the mouth and throat wherein some damage could possibly occur.
In all known prior art, ultrasonic dental-cleaning devices where an active element is not directly inserted into the mouth, the ultrasonic energy has been propagated along the vibrating element in a compressional mode. Under such propagation, the ultrasonic energy necessarily emanates from the tip of the member in a direction parallel to the longitudinal axis thereof. With such a device, it becomes extremely cumbersome if not impossible for use by an individual to clean his own teeth. For proper use by an individual upon his own teeth, it becomes necessary to radiate the energy transversely of the longitudinal axis of the vibrating element. To accomplish this in the prior art, the vibrating element along which the acoustical energy is propagated has been fitted with brushes, bent members, and the like. In all of these instances, the affect has been basically to merely provide a mechanical toothbrush/toothpaste-cleaning system. Although more effective than hand brushing, such systems still lacked easy, quick, and safe removal of bacteria, plaque, and other foreign matter from all surfaces of the teeth.
The best prior art known to applicants which illustrate the foregoing devices is disclosed in the following United States patents:
U.S. Pat. Nos. 3,760,799; 3,466,689; 3,401,690; 3,166,772; 3,514,328; 3,427,480; 3,847,662; 3,645,255; 3,380,446; 3,589,012; 2,980,123; 3,526,036; 3,154,890; 3,518,766; 3,522,801; 3,375,583; 3,593,425; 2,990,616; 3,488,788; 3,368,280; 3,703,037; 3,636,947; 3,863,628; 3,547,110; 4,012,842; 3,809,977; 3,375,820; 3,763,411; 3,335,443; 3,956,826.